1. Technical Field
The present invention relates to a projector.
2. Related Art
A projector having a first lens array, a second lens array and a superposing lens as a light integrator optical system is formerly known (for example, see JP-A-8-304739 (FIG. 11)). In accordance with the former projector, an illuminating light beam emitted from a light source device is divided into plural partial light beams by the first lens array having plural first small lenses. Each of these partial light beams is superposed in an illuminated area (an image forming area of an electro-optic modulator) by the functions of the superposing lens and the second lens array having plural second small lenses corresponding to the plural first small lenses. Therefore, it is possible to approximately uniform an in-plane light intensity distribution of light for irradiating the image forming area of the electro-optic modulator.
In the former projector, a conjugate point of the image forming area in the electro-optic modulator is located at the vertex of a lens curved surface in each first small lens of the first lens array. Therefore, for example, when dust is attached onto the lens curved surface of the first small lens and a flaw, etc. exist on the lens curved surface, images of such dust, a flaw, etc. are focused and formed on the image forming area. Therefore, the images of the dust, the flaw, etc. are included within an image projected on a projecting face. Accordingly, a problem exists in that image quality of the projecting image is reduced.